Locking device for chair-trays.



No. 848,891 PATENTED MAR; 26, 1907.

. v W. F. OLIVER. I

LOCKING DEVICE FOR CHAIR TRAYS.

APPLIGATION FILED DBO.15. 1905. q

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- No. 848,391. PATENTED MAR. 26, 1907.

W. P. OLIVER.

LOCKING DEVICE FOR CHAIR TRAYS. APPLIOATIQN FILED DEC. 15. 1905.

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WALTON F. OLIVER, OF TEMPLEFON, MASSACHUSETTS.

LOCKING DEVICE FOR CHAIR-TRAYS- Specification of Letters Patent.

Patented March 26, 1907.

Application filed December 15, 1905. Serial No. 291,840.

To aZZ whom it may concern.-

Be it known that I, WALTON F. OLIVER, of Templeton, in the county ofWorcester and State of Massachusetts, have invented certain new anduseful Improvements in Lock ing Devices for Chair-Trays, of which thefollowing is a specification.

This invention relates to an infants chair provided with a tray havingrearwardly-projecting arms which are hinged to the back of the chair,the arrangement being such that when the tray is not required for use itmay be swung over the backof the chair and de pend therefrom behind theseat. When the tray is required for use, it may be swung forward overthe chair-back and rest upon the forward portions of the chair-arms.

The invention has for its object to provide simple and effective meansfor locking the tray to the chair-arms in its operative position in suchmanner that while the tray can be readily unlocked and displaced bypressure applied at or near the forward edge of the tray it cannot beunlocked by any pressure which can be exerted by the occupant of thechair, thus preventing all liability of the unauthorized or undesiredunlocking of the tray while the chair is occupied.

The invention consists in the improvements which I will now proceed todescribe and claim.

Of the accompanying drawings, forming a part of this specification,Figurel represents a side elevation of a chair and a tray therefor towhich my invention is applied. Fig. 2 represents a section on line 2 2of Fig. 1 look ing upwardly and showing a bottom plan view of the trayand an embodiment of my invention applied thereto, the locking devicebeing shown in its position of engagement with the chairarms. Fig. 3represents a view similar to Fig. 2, showing the locking de vice in itsposition of disengagement from the chair-arms. Fig. 41 represents asection on line a 4 of Fig. 2. Fig. 5 represents a section on line 5 5of Fig. 2. Fig. 6 represents a modification.

The same letters of reference indicate the same parts in all thefigures.

In the drawings, 12 represents a tray to which are rigidly attachedcurved arms 13 13, the rear portions of which are pivoted at 14 to theback of the chair. WVhen the tray is in use, it occupies the positionrelatively to the back and arms of the chair shown in Fig. 1, the trayresting on the forward portions of the chair-arms 15. The outer ends ofsaid arms are provided with slots or notches 16, Fig. 5, whichconstitute locking members adapted to engage complemental lockingmembers carried by the tray. The construction thus far described iscommon and well known, and therefore forms no part of my invention.

In carrying out my invention I provide the tray with an improved lockingdevice adapted to engage the Slots 16 of the chairarms in such manner asto lock the tray securely in its operative position without lia bilityof its being unlocked by an infant sitting in the chair, the lockingdevice being of such character that it can be readily manipulated tosimultaneonsly disengage the tray from both arms of the chairby'pressure exerted at a portion of the tray which is inaccessible tothe occupant of the chair.

In the embodiment of my invention here shown for the purpose ofillustration the locking device comprises a single piece of resilientwire the end portions of which are bent to form two compressible loops17 17, each comprising an inner arm 18 and an outer arm 19, while thecentral or intermediate portion 20 is substantially U-shaped andprojects forwardly into suitable proximity to the forward edge of thetray. The outer ends of the loop-arms 18 are provided with eyes 21,adapted to receive attachingscrews which secure or anchor the lockingdevice to the under side of the tray, the arms 18 being, therefore,anchoring members. The loops 17 are offset at 22, so that the mainportions of the loops stand below the bottom of the tray, as shown inFigs. 4 and 5, the outer arms 19 of the loops being thus held inposition to spring into and engage the slots 16 of the chair arms, thesaid arms 19 constituting locking members. The U- shaped central portion20 is formed so that when the eyes 21 are secured to the tray the saidU-shaped portion will be under compression and in its effort to expandwill press the outer arms 19 of the loops backwardly toward the rearedge of the tray, so

that when the tray is in its operative position the loop-arms 19 will beheld yieldingly in engagement with the slotted ends of the chair-arms.The anchorage of the arms 18 to the tray is essential, such anchoragepreventing displacement of the outer portions of the arms 18 when theportion 20 is moved to compress the loops. The compression imparted tothe loops by a movement of the portion 20 is therefore held by theanchorage, so that the loops are enabled to effectively expand after theportion 20 is released.

23 23 represent stops affixed to the bottom of the tray and located insuch proximity to the rear arms 18 of the loops as to prevent bodilyforward movement of the loops to such an extent as to disengage the reararms of the loops from the slots of the chair-arms. In other words, ifthe occupant of the chair were to exert forward pressure against theloops they would be arrested by contact of the rear arms of the loopswith the stops 23 before the outer arms 19 can be disengaged from theslots of the chair-arms. It will be seen from the foregoing and byreference to Fig. 3 of the drawings that the outer arms 19 of the loopscan only be disengaged from the chair-arms by compression of the loops.This compression may be conveniently exerted by application of theoperators fingers to the U-shaped portion 20, as indicated in Fig. 3,this portion constituting a handle or finger-rest extension of the outerarms of the loops and being arranged so that pressure of the fingers canbe advantageously exerted upon it to compress the loops laterally andthus unlock the tray. It will be seen that provision is thus made forsimultaneously unlocking the tray from both arms of the chair and thatthis simultaneous action can not be conveniently caused by anyinstrumentality excepting a hand applied to the front portion of thetray and at the under side thereof, this portion being inaccessible tothe occupant of the chair.

My improved locking device possesses the following advantages: First, itrequires no change in the construction of the chair; secondly, it may bevery easily attached, only two attaching-screws being required; thirdly,its construction is very inexpensive, only one piece of wire beingrequired, and, fourthly, it is applicable to trays of various sizes andproportions. I do not limit myself, however, to the duplication of thelocking devices. It is obvious that only one of the loops here shown maybe used, the portions of the wire constituting the other loop beingutilized as means for holding the outer arm of the first-mentioned loopin its operative position.

In Fig. 6 I show as a modification the eyes 21 of the loops 17 engagedwith the stops 23, the rear arms of the loops being correspondinglyreduced in length. In Fig. 6 I also show the wire forming the outer endsof the loops provided with coils 25, which increase the resiliency ofthe loops, the outer arms 19 being shown as provided with offsetportions 26, which bear on the bottom of the tray and prevent the loopsfrom being tipped or deflected from the plane of the slots 16 of thechair-arms.

I claim- 1. A locking device for a chair-tray, having a compressibleloop, one arm of which is attached at one end .to the tray, andconstitutes an anchoring member, the other arm constituting a lockingmember adapted to engage a complemental locking member on a chair, andmeans for yieldingly expanding the loop to normally hold the lockingmember separated from the anchoring member and in its locking position,the free end of the loop having a finger-engaging extension adapted toreceive pressure to compress the loop and disengage the locking memberfrom the chair.

'2. A locking device for a chair-tray having a compressible loop theinner arm of which is attached to the tray, while the outer armconstitutes a locking member adapted to engage a complemental lockingmember on a chair and a stop adapted to engage the inner arm to preventdisengagement of the locking member from the chair by bodilydisplacement of the loop, and means for yieldingly maintaining the loopwith the outer arm in its locking position, the said outer arm having afinger-engaging rest or extension adapted to receive loop-compressingand outerarm-displacing pressure.

3. A locking device for a chair-tray having a resilient wire rod bent atits end portions to form two compressible loops each having an inner armattached to the tray and an outer arm constituting a locking memberadapted to engage a complemental locking member on a chair, and anintermediate resilient U- shaped portion connecting the outer arms ofthe loops and yieldingly maintaining the loops with their outer arms inlooking position, the said intermediate portion constituting afinger-rest adapted to receive loop-compressing pressure.

4. As an article of manufacture a resilient tray-locking rod bent at itsend portions to form two compressible loops each having an inner armprovided with an eye for engage ment with an attaching device, and anouter arm constituting a locking member adapted to engage a complementallocking member on a chair, and an intermediate resilient U- shapedportion connecting the outer arms of tray and movable sidewise on theiranelior- In testimony whereof I have afiixed my ages to and from theirlocking positions, and signature in presence of two Witnesses.

a resilient iin er-en agin member located between and conn cting? saidarms, and E VALTON OLIVER adapted to simultaneously retract the same,l/Vitnesses:

said member normally holding the arms in CARLETON A. FLETCHER, theirlocking positions. WILLIAM E. NORTON.

